Nesov, your writings are so hard to understand sometimes. Let me take this as an example and give you some detailed feedback. I hope it's useful to you to determine in the future where you might have to explain in more detail or use more precise language.

It's not you who should use UDT, it's the world.

Do you mean "it's not only you", or "it's the world except you"? If it's the latter, it doesn't seem to make any sense. If it's the former, it doesn't seem to answer Eliezer's objection.

This is a salient point of departure between FAI and humanity.

Do you mean FAI should use UDT, and humanity shouldn't?

FAI is not in the business of saying in words what you should expect.

Ok, this seems clear. (Although why not, if that would make me feel better?)

People are stuff of the world, not rules of the world or strategies to play by those rules.

By "stuff", do you mean "part of the state of the world"? And people do in some sense embody strategies (what they would do in different situations), so what do you mean by "people are not strategies"?

Rules and strategies don't depend on particular moves, they specify how to handle them, but plays consist of moves, of evidence. This very distinction between plays and strategies is the true origin of updatelessness. It is the fault to make this distinction that causes the confusion UDT resolves.

This part makes sense, but I don't see the connection to what Eliezer wrote.